Thermo-Oxidative and Combustion Analysis of a Light Oil, an Athabasca Bitumen and its Fractions: A New Approach

Date
2012-12-12
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Pressurized Differential Scanning Calorimetry (PDSC) and Thermo-gravimetric/ Differential Scanning Calorimetry (TG/DSC) have been widely employed as thermal analytical tools to investigate and fingerprint the distillation/thermal cracking and oxidation/combustion behavior of crude oils. TG/DSC analysis is often described in the literature as a tool for investigating in situ combustion or High Pressure Air injection (HPAI) processes. It must be understood that while this technique reveals useful information on the thermal behavior of crude oils in inert or oxidation environments, the low operating pressure associated with these tests limits their utility to a fingerprinting function. PDSC tests performed at pressures which are representative of reservoir conditions and with the oil in contact with native core material have been found to have more direct application for predicting the behavior of combustion projects. A series of TG/DSC and PDSC studies were performed to investigate and compare the distillation/thermal cracking/oxidation/combustion characteristics of a 37.5°API oil (light oil), an Athabasca bitumen, and Athabasca maltenes and asphaltenes fractions in contact with their respective native core materials. The oxidation/combustion characteristics as observed from the heat flow traces were classified in terms of Low Temperature Range (LTR), High Temperature Range (HTR) and Negative Temperature Gradient Region (NTGR). Temperatures at which the heat flow rates achieve local maximums in the LTR and HTR have been identified for each of the samples at the operating pressures and heating rates examined. The key observation from the study is that while the heat flow traces show similar behaviors within the LTR, HTR and NTGR, the actual values for the important parameters (peak temperatures, maximum heat flow rates, heat generated in the LTR and HTR) are dependent on the operating conditions of the specific test. Heat flow and mass loss traces as determined using the TG/DSC were used to calculate apparent heats of reaction traces. The range of values of the apparent heats of reactions as the temperatures pass through the LTR, NTGR, and HTR regions were used to interpret the nature of the mass loss mechanisms within the different temperature ranges.
Description
Keywords
Engineering--Chemical, Engineering--Petroleum
Citation
Rios Chiquillo, E. Y. (2012). Thermo-Oxidative and Combustion Analysis of a Light Oil, an Athabasca Bitumen and its Fractions: A New Approach (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/28313